While qualitatively our data suggest that the \(T\) -dependence of \(\sigma _{min}(T)\)  in suspended samples results from a low \(\tilde{n}\) , a quantitative description of \(\sigma _{min}\)  is complicated by the fact that \(k_F l_m>1\)  at small \(n\)  and a Boltzmann description may no longer be applicable. Such complicating factors are evident from a comparison between different annealed devices, which exhibit both a different magnitude and a different functional \(T\) -dependence as seen in Fig. 4. This suggests that the transport at the neutrality point in the suspended samples is dominated by extrinsic scattering. Interestingly, \(\sigma _{min}(T)\)  exhibits a \(T\) -dependence, which is much weaker than the \(\sigma _{min}\propto T^2\)  (solid line in Fig. 4), expected from a Boltzmann model [1]}, [2]}.
